Long-Term Debt - Narrative (Details)	6 Months Ended
May 31, 2021 USD ($) contract	Nov. 30, 2020 USD ($)
Debt Instrument [Line Items]
Long-term debt	$ 8,823,245,000	$ 8,352,039,000
Subsidiaries
Debt Instrument [Line Items]
Long-term debt	7,829,836,000	7,359,328,000
Structured notes \| Jefferies Group
Debt Instrument [Line Items]
Debt issued during period, principal amount, net of retirements	59,500,000
Structured notes \| Jefferies Group \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	1,819,975,000	1,712,245,000
Revolving Credit Facility \| Jefferies Group
Debt Instrument [Line Items]
Borrowings under credit facility	248,800,000
Revolving Credit Facility \| Jefferies Group \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	248,764,000	189,732,000
Bank loan obligations \| Jefferies Group
Debt Instrument [Line Items]
Debt principal amount	50,000,000.0
Vitesse Energy Finance Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	82,000,000.0	98,500,000
Maximum borrowing capacity	120,000,000.0
Vitesse Energy Finance Revolving Credit Facility \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	$ 81,502,000	97,883,000
Vitesse Energy Finance Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Percentage of proved reserve value of oil and gas properties	85.00%
Jefferies Group Secured Credit Facility \| Jefferies Group \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	$ 375,000,000	0
HomeFed Construction Loans \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	49,407,000	45,471,000
HomeFed Construction Loans \| HomeFed
Debt Instrument [Line Items]
Construction loan, maximum borrowing amount	$ 162,700,000
Weighted average interest rate	3.21%
Long-term debt	$ 50,800,000	46,200,000
LIBOR \| Bank loan obligations \| Jefferies Group
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
LIBOR \| Vitesse Energy Finance Revolving Credit Facility \| Vitesse Energy Finance \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
LIBOR \| Vitesse Energy Finance Revolving Credit Facility \| Vitesse Energy Finance \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.50%
LIBOR \| HomeFed Construction Loans \| HomeFed \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.15%
LIBOR \| HomeFed Construction Loans \| HomeFed \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.15%
Line of Credit \| Foursight Capital Credit Facilities
Debt Instrument [Line Items]
Long-term debt	$ 109,300,000	129,300,000
Line of Credit \| Foursight Capital Credit Facilities \| Subsidiaries
Debt Instrument [Line Items]
Long-term debt	$ 109,168,000	$ 129,000,000
Line of Credit \| Foursight Capital Credit Facilities \| Foursight Capital
Debt Instrument [Line Items]
Number of warehouse credit commitments \| contract	2
Maximum borrowing capacity	$ 175,000,000.0
Assets pledged for indebtedness	$ 135,900,000

Assets Pledged For Indebtedness

No definition available.

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- Definition

Construction Loan, Maximum Borrowing Amount

+ References

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- Definition

Debt Instrument, Issued During Period, Principal Amount, Net Of Retirements

+ References

No definition available.

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- Definition

Line Of Credit Facility, Collateral, Percentage Of Proved Reserve Value of Oil and Gas Properties

+ References

No definition available.

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- Definition

Number of Warehouse Credit Commitments

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

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